Wearable piezoresistive strain sensor based on graphene-coated three-dimensional micro-porous PDMS sponge

Young Jung,Donghwan Kim,Byunggeon Park,Jinhyoung Park,Hanchul Cho,Jongsoo Ko,Kyungkuk Jung,Jaehyuk Choi

doi:10.1186/s40486-019-0097-2

Abstract

We present a highly elastic and wearable piezoresistive strain sensor based on three-dimensional, micro-porous graphene-coated polydimethylsiloxane (PDMS) sponge suitable for being attached on human skin. The proposed strain sensors are simply fabricated by a sugar templating process and dip coating method based graphene ink in a facile and cost effective manner. The fabricated graphene-coated PDMS sponge shows highly stable mechanical properties in various tensile stress–strain test. A graphene thin film coated onto the backbone of PDMS sponges is used as the sensing materials of piezoresisitve strain sensors. The changes in resistance of the devices are highly stable, repeatable, and reversible when various strain is applied. Furthermore, the strain sensors show excellent sensing performance under different strain rate and mechanically robustness enough to be worked stably under repeated loads without any degradation.

Highlights

The proposed method for the fabrication of sensors is to use of nanomaterials such as Carbon Nanotubes (CNTs), Carbon Blacks (CBs), Graphene, Zinc Oxide Nanowires (ZnO zinc oxide nanowires (NWs)), Siliver Nanowires (AgNWs) that can be coupled with elastic polymer
We report a highly elastic and wearable strain sensor utilizing three-dimensional, micro-porous graphene-coated polydimethylsiloxane (PDMS) sponges that are capable of measuring strains
The surface properties of bare and graphene-coated PDMS sponge was studied by contact angle measurement

Summary

Introduction

There has been attracting attention in order to develop wearable sensors that can be applied to variety of applications including electronic skin [1, 2], soft robotics [3–5], health monitoring [6, 7], and human–machine interfaces [8]. *Correspondence: hc.cho@kitech.re.kr 1 Precision Machining Control Group, Korea Institute of Industrial Technology, 42‐7, Baegyang‐daero 804beon‐gil, Sasang‐gu, Busan 46938, Republic of Korea Full list of author information is available at the end of the article working range, the strain gauges are unable to detect large strain in wearable applications. Many studies have been proposed to coat or synthesize nanomaterials on porous sponges and use them as sensing materials of strain sensors based on piezoresistivity.

Results

Conclusion